Reduced-pressure systems, methods, and devices for simultaneously treating a plurality of tissue sites

ABSTRACT

Systems and methods for treating a plurality of tissue sites include a multi-port therapy unit. The multi-port therapy unit includes a plurality of patient-side ports each fluidly coupled to a plurality of conduits and a fluid reservoir fluidly coupled to the plurality of ports. A plurality of pressure sensors are associated with the plurality of patient-side ports to determining a pressure associated with each conduit. A controller is operatively coupled to the plurality of pressure sensors to receive treatment pressure data, monitor pressure for each pressure sensor of the plurality of pressure sensors, and signal an alarm condition if the pressure is outside of a pre-selected range. The system includes a reduced-pressure source fluidly coupled to a dressing at each tissue site through the multi-port therapy unit.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.13/681,731 filed Nov. 20, 2012, which claims priority to U.S.Provisional Patent Application No. 61/563,284 filed Nov. 23, 2011,entitled REDUCED-PRESSURE SYSTEMS, METHODS, AND DEVICES FORSIMULTANEOUSLY TREATING A PLURALITY OF TISSUE SITES, the disclosure ofwhich is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present disclosure relates generally to medical systems, devices,and methods for treating a patient with reduced pressure, and moreparticularly, but not by way of limitation, to medical systems, devices,and methods for simultaneously treating a plurality of tissue sites.

Description of Related Art

Clinical studies and practice have shown that providing reduced pressurein proximity to a tissue site augments and accelerates the growth of newtissue at the tissue site. The applications of this phenomenon arenumerous, but application of reduced pressure has been particularlysuccessful in treating wounds. This treatment (frequently referred to inthe medical community as “negative pressure wound therapy,” “reducedpressure therapy,” or “vacuum therapy”) provides a number of benefits,which may include faster healing and increased formulation ofgranulation tissue. At times, it may be necessary to treat a pluralityof tissue sites. This is particularly true of patients injured by burns,war, or other trauma. Moreover, the plurality of tissue sites may needto be treated in the field or during transportation.

SUMMARY

Systems, methods, and devices are presented that facilitate thesimultaneous treatment of a plurality of tissue sites with reducedpressure.

In an illustrative embodiment, a system for simultaneously treating aplurality of tissue sites on a patient is disclosed. The system includesa plurality of reduced-pressure dressings, and a plurality ofmulti-lumen reduced-pressure delivery conduits. Each multi-lumenreduced-pressure delivery conduit includes at least onepressure-sampling lumen and at least one reduced-pressure supply lumen.The system also includes a multi-port therapy unit. The multi-porttherapy unit includes a plurality of patient-side ports. Each of theplurality of patient-side ports is configured to fluidly couple with oneof the plurality of multi-lumen reduced-pressure delivery conduits andwith at least one of the pressure-sampling lumens and one of thereduced-pressure supply lumens therein. The multi-port therapy unit alsoincludes a fluid reservoir fluidly coupled to the plurality ofpatient-side ports, and a plurality of pressure sensors. The pluralityof pressure sensors are associated with the plurality of patient-sideports for determining a pressure associated with each of the pluralityof pressure-sampling lumens. The multi-port therapy unit furtherincludes a controller operatively coupled to the plurality of pressuresensors for receiving treatment pressure data from the plurality ofpressure sensors. The controller includes a microprocessor and memoryconfigured to monitor pressure for each of the plurality of pressuresensors and to signal an alarm condition if the pressure is outside of apre-selected range. The multi-port therapy unit also includes anelectrical source operatively coupled to the controller, and asupply-side port for receiving reduced pressure. The supply-side port isfluidly coupled to the fluid reservoir. The multi-port therapy unit alsoincludes an alarm indicator operatively coupled to the controller forindicating when the controller signals an alarm condition. The systemfurther includes a reduced-pressure source fluidly coupled to thesupply-side port.

In another illustrative embodiment, a method for treating a plurality oftissue sites on a patient is disclosed. The method deploys a pluralityof reduced-pressure dressings proximate to the plurality of tissue sitesand fluidly couples the plurality of reduced-pressure dressings to amulti-port therapy unit. The multi-port therapy unit includes aplurality of patient-side ports. Each of the plurality of patient-sideports is configured to fluidly couple with one of the plurality ofmulti-lumen reduced-pressure delivery conduits and with at least one ofthe pressure-sampling lumens and one of the reduced-pressure supplylumens therein. The multi-port therapy unit further includes a fluidreservoir fluidly coupled to the plurality of patient-side ports and aplurality of pressure sensors. The plurality of pressure sensors areassociated with the plurality of patient-side ports for determining apressure associated with each of the plurality of pressure-samplinglumens. The multi-port therapy unit further includes a controlleroperatively coupled to the plurality of pressure sensors for receivingtreatment pressure data from the plurality of pressure sensors. Thecontroller includes a microprocessor and memory configured to monitorpressure for each of the plurality of pressure sensors and to signal analarm condition if the pressure is outside of a pre-selected range. Anelectrical source is operatively coupled to the controller. Themulti-port therapy unit further includes a supply-side port forreceiving reduced pressure. The supply-side port is fluidly coupled tothe fluid reservoir, and an alarm indicator is operatively coupled tothe controller for indicating when the controller signals an alarmcondition. The method activates the multi-port therapy unit to deliverreduced pressure simultaneously to the plurality of reduced-pressuredressings and to monitor pressure for each of the plurality ofreduced-pressure dressings.

In still another illustrative embodiment, a system for simultaneouslytreating a plurality of tissue sites on a patient is disclosed. Thesystem includes a plurality of reduced-pressure dressings and aplurality of multi-lumen reduced-pressure delivery conduits. Eachmulti-lumen reduced-pressure delivery conduit includes at least apressure-sampling lumen and at least a reduced-pressure supply lumen.The system further includes a fluid storage device fluidly coupled tothe plurality of reduced-pressure dressings for receiving and at leasttemporarily storing fluids, and a multi-port therapy unit. Themulti-port therapy unit includes a controller and a plurality ofpatient-side ports. Each of the plurality of patient-side ports isconfigured to fluidly couple with one of the plurality of multi-lumenreduced-pressure delivery conduits and with at least one of thepressure-sampling lumens and one of the reduced-pressure supply lumenstherein. The multi-port therapy unit also includes a plurality ofreduced-pressure plenums, each of the plurality of reduced-pressureplenums associated with one of the plurality of patient-side ports. Themulti-port therapy unit further includes a plurality of treatmentpressure sensors. Each of the plurality of treatment pressure sensors isassociated with one of the plurality of patient-side ports fordetermining a pressure associated with the at least onepressure-sampling lumen in the multi-lumen reduced-pressure deliveryconduit associated with the patient-side port. Each treatment pressuresensor is operatively coupled to the controller to provide a treatmentpressure signal to the controller. The multi-port therapy unit alsoincludes a plurality of plenum pressure sensors. Each of the pluralityof plenum pressure sensors is associated with one of the plurality ofreduced-pressure plenums and is operatively coupled to the controllerfor supplying a plenum pressure signal. The multi-port therapy unitfurther includes a first plurality of control valves fluidly coupledbetween each of the plurality of reduced-pressure plenums and anassociated patient-side port. Each of the first plurality of controlvalves is operatively coupled to the controller so that each of thefirst plurality of control valves may be controlled by the controller.The multi-port therapy unit also includes a main vacuum source fluidlycoupled to each of the plurality of plenums for supplying reducedpressure to each of the plurality of reduced-pressure plenums, and asecond plurality of control valves fluidly coupled between each of theplurality of reduced-pressure plenums and the main vacuum source. Thecontroller is operative to regulate the reduced pressure supplied fromthe plurality of reduced-pressure plenums to the plurality ofpatient-side ports by controlling the first plurality of control valvesand to regulate the reduced pressure supplied to the plurality ofreduced-pressure plenums using the second plurality of control valves.

In yet another illustrative embodiment, a system for simultaneouslytreating a plurality of tissue sites on a patient is disclosed. Thesystem includes a plurality of reduced-pressure dressings and aplurality of multi-lumen reduced-pressure delivery conduits. Eachmulti-lumen reduced-pressure delivery conduit includes at least apressure-sampling lumen and at least a reduced-pressure supply lumen.The system also includes a fluid storage device fluidly coupled to theplurality of reduced-pressure dressings for receiving fluids therefromand a multi-port therapy unit. The multi-port therapy unit includes aplurality of pressure ports. Each of the plurality of pressure ports isconfigured to fluidly couple with at least one of the pressure-samplinglumens of the plurality of multi-lumen reduced-pressure deliveryconduits. The multi-port therapy unit also includes a treatment pressuresensor fluidly coupled to the plurality of pressure sampling lumensassociated with the plurality of multi-lumen reduced-pressure deliveryconduits by a plurality of delivery conduits. The multi-port therapyunit further includes a valve means fluidly coupled to the treatmentpressure sensor and the plurality of pressure ports for selectivelycontrolling the flow from each of the plurality of pressure ports to thetreatment pressure sensor. In addition, the multi-port therapy unitincludes a reduced-pressure source fluidly coupled to the plurality ofreduced-pressure dressings, and a controller operatively coupled to thetreatment pressure sensor, the plurality of valves, and thereduced-pressure source. The controller is configured to monitor thereduced pressure of each of the plurality of pressure-sampling lumensassociated with the plurality of multi-lumen reduced-pressure deliveryconduits and in response to control the reduced pressure delivered bythe reduced-pressure source.

In still another illustrative embodiment, a system for simultaneouslytreating a plurality of tissue sites on a patient is disclosed. Thesystem includes a plurality of reduced-pressure dressings and aplurality of multi-lumen reduced-pressure delivery conduits. Eachmulti-lumen reduced-pressure delivery conduit includes at least apressure-sampling lumen and reduced-pressure supply lumen. The systemalso includes a fluid storage device fluidly coupled to the plurality ofreduced-pressure dressings for receiving fluids therefrom and amulti-port therapy unit. The multi-port therapy unit includes acontroller and a plurality of pressure ports. Each of the plurality ofpressure ports is configured to fluidly couple with at least one of thepressure-sampling lumens of the plurality of multi-lumenreduced-pressure delivery conduits. The multi-port therapy unit furtherincludes a plurality of treatment pressure sensors fluidly coupled tothe plurality of pressure ports and operatively coupled to thecontroller, and a reduced-pressure source fluidly coupled to theplurality of reduced-pressure dressings. The controller is operativelycoupled to the plurality of treatment pressure sensors and thereduced-pressure source. The controller is configured to monitor thereduced pressure of each of the plurality of pressure-sampling lumensassociated with the plurality of multi-lumen reduced-pressure deliveryconduits and to control the reduced pressure delivered by thereduced-pressure source.

Aspects, features, and advantages of the illustrative embodiments willbecome apparent with reference to the drawings and detailed descriptionthat follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view (with a portion shown in elevationview) of an illustrative embodiment of a system for simultaneouslytreating a plurality of tissue sites on a patient;

FIG. 2 is an elevation view of an illustrative embodiment of amulti-port therapy unit and an illustrative reduced-pressure source fromFIG. 1 ;

FIG. 3 is a cross-sectional view (with a portion shown as a schematicdiagram) of an illustrative embodiment of a system for simultaneouslytreating a plurality of tissue sites on a patient;

FIG. 4 is a cross-sectional view of an illustrative embodiment of areduced-pressure plenum for use as an aspect of the system of FIG. 3 ;

FIG. 5 is a cross-sectional view (with a portion shown as a schematicdiagram) of an illustrative embodiment of a system for simultaneouslytreating a plurality of tissue sites on a patient;

FIG. 6 is a schematic diagram of a portion of an illustrative embodimentof a system for simultaneously treating a plurality of tissue sites on apatient;

FIG. 7 is a schematic pressure-time graph for illustrating a method foridentifying a leak in system for simultaneously treating a plurality oftissue sites on a patient;

FIG. 8 is a schematic pressure-time graph for illustrating a method foridentifying a leak in a system for simultaneously treating a pluralityof tissue sites on a patient;

FIG. 9 is a perspective view of an illustrative embodiment of amulti-port therapy unit;

FIG. 10 is a side elevation view of the multi-port therapy unit of FIG.9 ;

FIG. 11 is a rear elevation view of the multi-port therapy unit of FIG.9 ;

FIG. 12 is a perspective view of an illustrative embodiment of amulti-port therapy unit;

FIG. 13 is a front elevation view of the multi-port therapy unit of FIG.12 ;

FIG. 14 is a rear elevation view of the multi-port therapy unit of FIG.12 ;

FIG. 15 is a side elevation view of the multi-port therapy unit of FIG.12 ;

FIG. 16 is a perspective view of an illustrative embodiment of amulti-port therapy unit;

FIG. 17 is a side elevation view of the multi-port therapy unit of FIG.16 ;

FIG. 18 is a rear elevation view of the illustrative multi-port therapyunit of FIG. 16 ;

FIG. 19 is a perspective view of an illustrative embodiment of amulti-port therapy unit;

FIG. 20 is a side elevation view of the multi-port therapy unit of FIG.19 ; and

FIG. 21 is a rear elevation view of the multi-port therapy unit of FIG.19 .

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In the following detailed description of illustrative, non-limitingembodiments, reference is made to the accompanying drawings that form apart hereof. These embodiments are described in sufficient detail toenable those skilled in the art to practice the invention, and it isunderstood that other embodiments may be utilized and that logical,structural, mechanical, electrical, and chemical changes may be madewithout departing from the spirit or scope of the invention. To avoiddetail not necessary to enable those skilled in the art to practice theembodiments described herein, the description may omit certaininformation known to those skilled in the art. The following detaileddescription is not to be taken in a limiting sense, and the scope of theillustrative embodiments is defined only by the appended claims.

Referring now to the figures and primarily to FIGS. 1-2 , anillustrative embodiment of a system 100 for simultaneously treating aplurality of tissue sites 102 is presented. Each tissue site 102 may bethe bodily tissue of any human, animal, or other organism, includingbone tissue, adipose tissue, muscle tissue, dermal tissue, vasculartissue, connective tissue, cartilage, tendons, ligaments, or any othertissue. Treatment of tissue sites 102 may include removal of fluids,e.g., exudate or ascites. While numerous tissue sites, sizes, and depthsmay be treated with the system 100, the system 100 is shown treatingtissue sites 102 in the form of wounds. The wounds are shown forillustrative purposes extending through epidermis 108, dermis 110, andinto subcutaneous tissue 112. Other depths or types of wounds or, moregenerally, tissue sites may be treated. While three tissue sites 102 areshown for illustration purposes, it should be understood that any numberof tissue sites—typically two or greater—may be treated with the system100.

The system 100 includes a plurality of reduced-pressure dressings 114deployed on the plurality of tissue sites 102. Each of the plurality ofreduced-pressure dressings 114 may be any kind of dressing that allowsreduced pressure to be delivered to the tissue site 102 associated withthe reduced-pressure dressing 114 and that is operable to remove fluidsfrom the tissue site 102. In one illustrative embodiment, eachreduced-pressure dressing 114 includes a manifold 116, a sealing member118, and a reduced-pressure interface 120. The sealing member 118 isreleasably coupled to the tissue site 102 using an attachment device122. The attachment device 122 may take numerous forms. For example, theattachment device 122 may be a medically acceptable, pressure-sensitiveadhesive that extends about a periphery, a portion, or the entiresealing member 118; a double-sided drape tape; paste; hydrocolloid;hydro-gel; silicone gel, oraganogel, or other sealing devices orelements. For each reduced-pressure dressing 114, the sealing member 118creates a sealed space 124 containing the manifold 116 and the tissuesite 102 to be treated.

For each reduced-pressure dressing 114, the manifold 116 is a substanceor structure that is provided to assist in applying reduced pressure to,delivering fluids to, or removing fluids from the associated tissue site102. The manifold 116 includes a plurality of flow channels or pathwaysthat distribute fluids provided to and removed from the tissue site 102around the manifold 116. In one illustrative embodiment, the flowchannels or pathways are interconnected to improve distribution offluids provided to or removed from the tissue site 102. The manifold 116may comprise, for example, one or more of the following: a biocompatiblematerial that is capable of being placed in contact with the tissue site102 and distributing reduced pressure to the tissue site 102; devicesthat have structural elements arranged to form flow channels, such as,for example, cellular foam, open-cell foam, porous tissue collections,liquids, gels, and foams that include, or cure to include, flowchannels; porous materials, such as foam, gauze, felted mat, or anyother material suited to a particular biological application; or porousfoam that includes a plurality of interconnected cells or pores that actas flow channels, e.g., a polyurethane, open-cell, reticulated foam suchas GranuFoam® material manufactured by Kinetic Concepts, Incorporated ofSan Antonio, Tex.; a bioresorbable material; or a scaffold material. Insome situations, the manifold 116 may also be used to distribute fluidssuch as medications, antibacterials, growth factors, and varioussolutions to the tissue site 102. Other layers may be included in or onthe manifold 116, such as absorptive materials, wicking materials,hydrophobic materials, and hydrophilic materials.

In one illustrative, non-limiting embodiment, the manifold 116 may beconstructed from a bioresorbable material that can remain in a patient'sbody following use of the reduced-pressure dressing 114. Suitablebioresorbable materials may include, without limitation, a polymericblend of polylactic acid (PLA) and polyglycolic acid (PGA). Thepolymeric blend may also include without limitation polycarbonates,polyfumarates, and capralactones. The manifold 116 may further serve asa scaffold for new cell-growth, or a scaffold material may be used inconjunction with the manifold 116 to promote cell-growth. A scaffold isa substance or structure used to enhance or promote the growth of cellsor formation of tissue, such as a three-dimensional porous structurethat provides a template for cell growth. Illustrative examples ofscaffold materials include calcium phosphate, collagen, PLA/PGA, coralhydroxy apatites, carbonates, or processed allograft materials.

The sealing member 118 may be any material that provides a fluid seal. Afluid seal is a seal adequate to maintain reduced pressure at a desiredsite given the particular reduced-pressure source or subsystem involved.The sealing member 118 may be, for example, an impermeable orsemi-permeable, elastomeric material. For semi-permeable materials, thepermeability must be low enough that for a given reduced-pressuresource, the desired reduced pressure may be maintained. The sealingmember 118 may be discrete pieces for each reduced-pressure dressing 114or may be one continuous sheet used for all the plurality ofreduced-pressure dressings 114.

Each of the plurality of reduced-pressure interfaces 120 is fluidlycoupled to the associated sealed space 124 for the tissue site 102. Thereduced-pressure interfaces 120 may each be any device for deliveringreduced pressure to the associated sealed space 124. For example, eachof the reduced-pressure interfaces 120 may comprise one of thefollowing: a T.R.A.C.® Pad or Sensa T.R.A.C.® Pad available from KCI ofSan Antonio, Tex.; or another device or tubing. A plurality ofmulti-lumen reduced-pressure delivery conduits 126 are fluidly coupledto the plurality of reduced-pressure interfaces 120 in a one-to-onefashion. Each of the plurality of multi-lumen reduced-pressure deliveryconduits 126 has a first end 127 and a second end 129. Each first end127 of the multi-lumen reduced-pressure delivery conduits 126 is fluidlycoupled to a multi-port therapy unit 128. Each of the plurality ofmulti-lumen reduced-pressure delivery conduits 126 may include at leastone pressure-sampling lumen and at least one reduced-pressure supplylumen. The pressure-sampling lumen provides a pressure for determiningthe pressure or approximate pressure at the associated reduced-pressuredressing 114. The reduced-pressure supply lumen delivers the reducedpressure to the reduced-pressure dressing 114 and receives fluidstherefrom. The second end 129 of each multi-lumen reduced-pressuredelivery conduit 126 is fluidly coupled to a respective reduced-pressureinterface 120.

The multi-port therapy unit 128 provides reduced pressure through themulti-lumen reduced-pressure delivery conduits 126 and reduced-pressureinterfaces 120 to the sealed spaces 124. In addition, the multi-porttherapy unit 128 receives pressure from the at least onepressure-sampling lumen of each of the plurality of multi-lumenreduced-pressure delivery conduits 126 and determines the pressurethereof.

Reduced pressure includes a pressure less than the ambient pressure at atissue site that is being subjected to treatment. In most cases, thisreduced pressure will be less than the atmospheric pressure at which thepatient is located. Alternatively, the reduced pressure may be less thana hydrostatic pressure at the tissue site. Unless otherwise indicated,quantitative values of pressure stated herein are gauge pressures. Thereduced pressure delivered may be constant or varied (patterned orrandom) and may be delivered continuously or intermittently. Althoughthe terms “vacuum” and “negative pressure” may be used to describe thepressure applied to the tissue site, the actual pressure applied to thetissue site may be more than the pressure normally associated with acomplete vacuum. Consistent with the use herein, unless otherwiseindicated, an increase in reduced pressure or vacuum pressure typicallyrefers to a reduction in absolute pressure.

The multi-port therapy unit 128 includes a plurality of patient-sideports 130. Each of the plurality of patient-side ports 130 is configuredto fluidly couple to one of the multi-lumen reduced-pressure deliveryconduits 126 and in particular with at least one of thepressure-sampling lumens and one of the reduced-pressure supply lumensof the plurality of multi-lumen reduced-pressure delivery conduits 126.Patient-side ports 130 not in use may be sealed by a cap 131.

A fluid reservoir 134 is fluidly coupled to the plurality ofpatient-side ports 130 to provide reduced pressure thereto and receivefluids therefrom. A drain conduit 135 may fluidly couple the fluidreservoir 134 to an exterior for draining the fluid reservoir 134. Avalve 137 associated with the drain conduit 135 selectively controlsfluid exiting the drain conduit 135. The valve 137 may be manual or maybe automated and coupled to a controller 136. Unless otherwiseindicated, as used throughout this document, “or” does not requiremutual exclusivity.

The multi-port therapy unit 128 also includes a plurality of pressuresensors 132, or pressure transducers, that provide a treatment pressuresignal to the controller 136. The controller 136 may be a printed wireassembly (PWA) or an application specific integrated circuit (ASIC) witha microprocessor and memory or other control device. The plurality ofpressure sensors 132 are associated with the plurality of patient-sideports 130 for determining a pressure associated with each of theplurality of patient-side ports 130 and typically with thepressure-sampling lumen therein that carries the approximate pressure atthe reduced-pressure dressing 114. Pressure associated with each of theplurality of patient-side ports 130 may include the pressure at the portitself or proximate the port in an internal conduit. In any event, eachpressure sensor 132 measures pressure a respective pressure-samplinglumen.

The controller 136 is operatively coupled to the plurality of pressuresensors 132 for receiving treatment pressure data from the plurality ofpressure sensors 132. The controller 136 includes a microprocessor andmemory configured to monitor pressure for each of the plurality ofpressure sensors 132 and to signal an alarm condition if the pressureleaves a desired range or goes below a minimum reduced pressurethreshold (i.e., the absolute pressure rises above a threshold). Thecontroller 136 is electrically coupled to an electrical power source138, which may be a battery or fixed power line, for example. A userinterface 140 is operatively coupled to the controller 136 for providinginformation readouts or for receiving user inputs.

The multi-port therapy unit 128 may include a plurality of visualindicators 142. The visual indicators 142 visually alert users when apressure below a first threshold exists (i.e., above an absolutepressure threshold) at one of the plurality of patient-side ports 130.

The multi-port therapy unit 128 also includes a supply-side port 144 forreceiving reduced pressure. The supply-side port 144 is fluidly coupledto the fluid reservoir 134 such as by an internal conduit 146. Thesupply-side port 144 is also fluidly coupled by a conduit 148 to areduced-pressure source 150.

The reduced-pressure source 150 may be any device for supplying areduced pressure, such as a vacuum pump, wall suction, or other source.While the amount and nature of reduced pressure applied to a tissue sitewill typically vary according to the application, the reduced pressurewill typically be between −5 mm Hg (−667 Pa) and −500 mm Hg (−66.7 kPa)and more typically between −75 mm Hg (−9.9 kPa) and −300 mm Hg (−39.9kPa). In some embodiments, the reduced-pressure source 150 may be aV.A.C. Freedom, V.A.C. ATS, InfoVAC, ActiVAC, ABThera, or V.A.C. Ultatherapy units available from KCI of San Antonio, Tex.

In operation according to one illustrative embodiment, thereduced-pressure source 150 is fluidly coupled to the supply-side port144 of the multi-port therapy unit 128. The caps 131, or sealing caps,are removed from the plurality of patient-side ports 130 in a numbercorresponding to the number of tissue sites 102 that are to be treated.The first ends 127 of the plurality of multi-lumen reduced-pressuredelivery conduits 126 are coupled to the uncapped members of theplurality of patient-side ports 130. The plurality of reduced-pressuredressings 114 are deployed on the plurality of tissue sites 102. Thesecond ends 129 of the plurality of multi-lumen reduced-pressuredelivery conduits 126 are fluidly coupled to the plurality ofreduced-pressure dressings 114. The reduced-pressure source 150 isactivated to supply reduced pressure to the fluid reservoir 134 and tothe tissue sites 102. As liquids are removed from the tissue sites 102,the liquids begin to fill the fluid reservoir 134. Optionally, afterfluid reservoir 134 is full, the fluid may continue into a fluidreservoir contained within the reduced-pressure source 150.Alternatively, a hydrophobic or oleophobic filter may be included aspart of the supply-side port 144 to prevent liquids from reaching thereduced-pressure source 150.

The multi-port therapy unit 128 monitors pressure at the tissue sites102 for each of the connected reduced-pressure dressings 114. Eachpressure sensor 132 develops a treatment pressure signal that isdelivered to the controller 136 for monitoring. The microprocessor andmemory or other aspects of controller 136 are used to monitor thetreatment pressure signals to confirm compliance with the desiredpressure range. The pressure in each tissue site 102 may be displayed onthe user interface 140 constantly or with a cycled pattern.Alternatively or in addition, separate multi-colored LED indicators maybe included to provide a quick color indication of pressure and statusat each of the plurality of patient-side ports 130. For example, themulti-colored LED indicators may be able to assume the colors green,yellow, and red. The controller 136 may be programmed to produce a greenlight when the pressure is between −75 mm Hg and −150 mm Hg. A yellowlight may be signaled if the wound pressure declines (i.e., losesreduced pressure so that pressure is greater on an absolute pressurescale) indicating a dressing leak. A red light may be used to indicatethe wound pressure is below a reduced pressure threshold (e.g., −40 mmHg) and is not providing adequate therapy. A flashing red light may meanthat an over pressure (e.g., more negative than −200 mm Hg) has beenapplied. In this regard, a relief valve may also be included. Under thisillustrative example, if a yellow or red light is given, the caregivermay find and address a leak that is in the associated reduced-pressuredressing 114, disconnect the multi-lumen reduced-pressure deliveryconduit 126 associated with that particular reduced-pressure dressing114 and reattach the cap 131 to avoid compromising the reduced pressureavailable for other tissue sites 102. In addition, the caregiver mayconnect a separate therapy unit (reduced pressure source and fluidreservoir) to the apparently leaking reduced-pressure dressing 114 sothat reduced pressure may continue to be supplied until a moreconvenient time is available for addressing the situation.

The controller 136 may also optionally activate an audible alarm 152,but given tight quarters for many transportation operations, thisfeature may be turned off or not included. Typically, if it is a desireto purge the plurality of multi-lumen reduced-pressure delivery conduits126, they will be purged together. If the red light is indicated, thecaregiver checks the multi-lumen reduced-pressure delivery conduits 126for blockage and replaces any blocked conduits if necessary.

In one illustrative embodiment, the fluid reservoir 134 in themulti-port therapy unit 128 is an off-the-shelf canister. In otherembodiments, the fluid reservoir 134 may have a minimal size, and theplurality of reduced-pressure dressings 114 may include absorbents tohold liquids at the dressing.

The multi-port therapy unit 128 may be a collapsible unit to minimizespace requirements. The multi-port therapy unit 128 may expand as itfills with liquids. In one illustrative embodiment, eachreduced-pressure dressing 114 includes an absorbent layer for storingliquids in the reduced-pressure dressing 114. The absorbent layer may bemade from super absorbent fibers. The super absorbent fibers may retainor bond to the liquid in conjunction with a physical or chemical changeto the fibers. In one non-limiting example, the super absorbent fibermay include the Super Absorbent Fiber (SAF) material from TechnicalAbsorbents, Ltd. of Grimsby, United Kingdom, or the like. The absorbentlayer may be a sheet or mat of fibrous material in which the fibersabsorb liquid from the tissue site 102. The structure of the absorbentlayer that contains the fibers may be either woven or non-woven. Thefibers in the absorbent layer may gel upon contact with the liquid,thereby trapping the liquid. Spaces or voids between the fibers mayallow reduced pressure that is applied to the absorbent layer to betransferred within and through the absorbent layer. In one illustrativeembodiment, the fiber density of the fibers in the absorbent layer maybe approximately 1.4 grams per millimeter.

Optionally, a positive pressure exhaust from a vacuum pump in thereduced-pressure source 150 may be routed into channels that arepressurized at a greater pressure than the reduced pressure gradientwithin the fluid reservoir 134 such that the fluid reservoir 134 has astructure that inflates around it. Alternatively, the chambers may besealed at ambient pressure, so when an aircraft transporting a patientusing the system 100 reaches altitude, the reduced pressure at altitudemay cause a pressure differential that fills the channels with higherpressure air.

The fluid reservoir 134 of the multi-port therapy unit 128 may include atortuous path such that fluid may not easily reflux from channel tochannel. This may take the form of an opening from a pathway of a secondbaffle, or series of baffles within a rigid section of the fluidreservoir 134. The tortuous paths may take the form of small pieces ofabsorbent, non-woven looking material, or a small-pore open-celled foamacting as a barrier to low pressure reflux or fluids. By having asmall-pored, open foam acting as a baffle over each channel throughwhich the fluids entering the fluid reservoir flow, one is using the“adhesive” effect of the fluid to the foam to reduce the risk of fluidswithin the fluid reservoir being refluxed due to small changes inpressure bias. Essentially, one would expect the fluids to prefer tostay on and within the foam structure during the period of time of anysignificant pressure imbalance.

There may be incorporated into the multi-port therapy unit 128 a varietyof valves that allow fluid and air to flow in one direction into thefluid reservoir 134 but prevents these same fluids from reverse flow.Such valves, commonly known as check-valves, include flat/flap valvesand duck-bill valves.

In one illustrative embodiment, the fluid reservoir 134 may be anabsorbent pouch. The fluid reservoir may be a pouch containing anabsorbent layer such as the one previously mentioned.

The supply-side port 144 may include a hydrophobic or oleophobic filter.The hydrophobic filter prevents fluids from being passed to thereduced-pressure source 150. The hydrophobic filter is periodicallychanged. The hydrophobic filter may be included as part of a fluidreservoir 134 and replaced when the fluid reservoir 134 is replaced. Ifthe fluid reservoir 134 becomes full, at times it may be desirable todrain some of the liquids therein. For this reason, the valve 137 may beopened and fluids removed through the drain conduit 135. If reducedpressure therapy is occurring during the draining process, a valve thatprevents reduced pressure from entering the supply-side port 144 may beincorporated and used to prevent the bleeding of reduced pressure. Ifthe fluid reservoir 134 includes an absorbent in the fluid reservoir134, an osmotic membrane may be used to have a fluid gathering sectionthat allows easy draining of that portion. In other words, water isseparated from the exudate such that the water may be discarded.

The ports 130, 144 may be configured to be “connector-less” connections.Shut-off valves may be incorporated into the connectors to minimize lossof vacuum during connecting and disconnecting.

In an alternative embodiment, the pressure sensors 132 may be removedfrom the multi-port therapy unit 128 and placed on the plurality ofreduced-pressure dressings 114. This may be more desirable withinexpensive pressure sensors. Such an approach would eliminate the needfor blockage detectors and allow specific tissue site pressuremonitoring with more accuracy. The fluid reservoir 134 may be removedfrom the multi-port therapy unit 128 for disposal. This leaves theremaining components for refurbishing and reuse according to oneillustrative embodiment.

Referring now primarily to FIG. 3 , another illustrative embodiment of asystem 200 for simultaneously treating a plurality of tissue sites 202is presented. The plurality of tissue sites 202, plurality ofreduced-pressure dressings 214, and many other aspects of the system 200are analogous to those in FIG. 1 . While numerous tissue sites, sizes,and depths may be treated with the system 200, the system 200 is showntreating tissue sites 202 in the form of wounds. The wounds are shownfor illustrative purposes extending through epidermis 208, dermis 210,and into subcutaneous tissue 212. Other depths or types of wounds or,more generally, tissue sites may be treated. While five tissue sites 202are shown for illustration purposes, it should be understood that anynumber of tissue sites—typically two and greater—may be treated with thesystem 200.

The system 200 includes the plurality of reduced-pressure dressings 214deployed on the plurality of tissue sites 202. Each of the plurality ofreduced-pressure dressings 214 may be any kind of dressing that allowsreduced pressure to be delivered to the tissue site 202 associated withthe reduced-pressure dressing 214 and that is operable to remove fluidsfrom the tissue site 202. In one illustrative embodiment, eachreduced-pressure dressing 214 includes a manifold 216, a sealing member218, and a reduced-pressure interface 220. The sealing member 218 isreleasably coupled to the tissue site 202 using an attachment device222. The attachment device 222 may take numerous forms, such as thosepreviously mentioned. The sealing member 218 creates a sealed space 224containing the manifold 216 and the tissue site 202 to be treated. Thesecomponents are analogous to those in FIG. 1 .

The reduced-pressure dressings 214 are fluidly coupled to a multi-porttherapy unit 228 by a plurality of multi-lumen reduced-pressure deliveryconduits 226. Each multi-lumen reduced-pressure delivery conduit 226 mayinclude at least one pressure-sampling lumen and at least onereduced-pressure supply lumen. Each multi-lumen reduced-pressuredelivery conduit 226 has a first end 227 and a second end 229. The firstends 227 are fluidly coupled to the multi-port therapy unit 228 at aplurality of patient-side ports 230. As in FIG. 1 , each patient-sideport 230 that is not used may have a cap (see 131 in FIG. 1 ) coveringthe patient-side port. Each of the plurality of patient-side ports 230is configured to fluidly couple with one of the plurality of multi-lumenreduced-pressure delivery conduits 226 and have at least one of thepressure-sampling lumens and one of the reduced-pressure supply lumensfluidly coupled. The pressure-sampling lumen is fluidly coupled to oneof a plurality of treatment pressure sensors 232.

A fluid storage device is fluidly coupled to each of the plurality ofmulti-lumen reduced-pressure delivery conduits 226. The fluid storagedevice is fluidly coupled to the plurality of reduced-pressure dressings214 for receiving and at least temporarily storing fluids therefrom. Thefluid storage device may be one or more of the following: a singlereservoir (not explicitly shown but analogous to 134 in FIGS. 1-2 )fluidly coupled to each the multi-lumen reduced-pressure deliveryconduits 226, a plurality of fluid reservoirs 234 (only one is shown forillustration purposes) associated with the multi-port therapy unit 228,a plurality of in-line canisters 235 (only one is shown for illustrationpurposes), a plurality of sections within one large canister which arespecific to each wound, or a plurality of absorbent layers associatedwith or forming part of the plurality of reduced-pressure dressings 214.

The multi-port therapy unit 228 includes a controller 236, the pluralityof patient-side ports 230, and a plurality of reduced-pressure plenums256. Each of the plurality of reduced-pressure plenums 256 is associatedwith one of the plurality of patient-side ports 230. Each plenum of theplurality of reduced-pressure plenums 256 is a pressure vessel forholding reduced pressure. Each plenum may have a fixed volume or avariable volume. With respect to the latter, as shown in FIG. 4 , in oneillustrative embodiment, each plenum of the plurality ofreduced-pressure plenums 256 may be formed with a moveable wall 258 thatis biased outward by biasing devices 260 to help maintain reducedpressure in the interior of the reduced-pressure plenum 256. The biasingdevice 260 may be a spring compressed shorter than its free length, apositively charged cylinder, or other biasing device. Each plenum mayhave a fixed volume between about 50 cc and about 400 cc, for example.

The multi-port therapy unit 228 also includes the plurality of treatmentpressure sensors 232. Each of the plurality of treatment pressuresensors 232 is associated with one of the plurality of patient-sideports 230 for determining a pressure associated with at least onepressure-sampling lumen in the multi-lumen reduced-pressure deliveryconduit 226 associated with the patient-side port 230. Each treatmentpressure sensor 232 is operatively coupled to the controller 236 toprovide a treatment pressure signal to the controller 236.

The multi-port therapy unit 228 also includes a plurality of plenumpressure sensors 262. Each of the plurality of plenum pressure sensors262 is associated with one of the plurality of reduced-pressure plenums256 and is operatively coupled to the controller 236 for supplying aplenum pressure signal.

The multi-port therapy unit 228 also includes a first plurality ofcontrol valves 264 fluidly coupled between each of the plurality ofreduced-pressure plenums 256 and an associated patient-side port 230.The plurality of first control valves 264 may comprise a plurality ofproportional valves. Each of the first plurality of control valves 264is operatively coupled to the controller 236 so that each of the firstplurality of control valves 264 may be controlled by the controller 236.The first plurality of control valves 264 controls the delivery ofreduced pressure from the reduced-pressure plenums 256 into theplurality of multi-lumen reduced-pressure delivery conduits 226. Abacteria filter may be associated with each of the first plurality ofcontrol valves 264. Alternatively or in addition, a bacteria filter maybe placed at the ports 230 or if an in-line canister is used as part ofthat structure.

The multi-port therapy unit 228 also includes a main vacuum source 266fluidly coupled to each of the plurality of reduced-pressure plenums 256for charging the reduced-pressure plenums 256, i.e., supplying reducedpressure to each of the plurality of reduced-pressure plenums 256. Themain vacuum source 266 is typically a single vacuum pump but could alsobe a wall supply of reduced pressure or a multi-pump subsystem. If avacuum pump, the main vacuum source 266 may receive electrical powerfrom an electrical power source 238. The main vacuum source 266 cancharge each of the plurality of reduced-pressure plenums 256 withreduced pressure. The stored reduced pressure is used to deliverregulated reduced pressure to the tissue sites 202. In one illustrativeembodiment, the reduced pressure in each reduced-pressure plenum 256 isgreater (more negative on a pressure scale) than −400 mm Hg.

The multi-port therapy unit 228 also includes a second plurality ofcontrol valves 268 fluidly coupled between each of the plurality ofreduced-pressure plenums 256 and the main vacuum source 266. Theplurality of second control valves 268 may comprise proportional valves.The second plurality of control valves 268 controls the introduction ofreduced pressure into the reduced-pressure plenums 256. The secondplurality of control valves 268 may have a hydrophobic filter associatedwith each to prevent liquids from reaching the main vacuum source 266.

Each of the plurality of first control valves 264 is controlled toregulate the reduced pressure down to the pressure selected by thecaregiver for a respective channel and tissue site 202. Optionally, themulti-lumen reduced-pressure delivery conduits 226 or connector mayinclude an automatic shut-off valve to isolate an individual line for adressing change without interacting with the user interface associatedwith the controller 236. An indicator could be provided on each line tohelp isolate leaks—one implementation may be a green/yellow/redindicator that is based on the controller's calculation of recharge ratefor a given plenum module, in conjunction with information about theproportional valve set point required to maintain the selected therapyreduced pressure. Multi-lumen reduced-pressure delivery conduits 226 maybe color-coded to aid in therapy management.

The controller 236 may be a printed wire assembly (PWA), for example, oran application specific integrated circuit (ASIC) with a microprocessorand memory or other control device. The controller 236 is operative toregulate the reduced pressure supplied from the plurality ofreduced-pressure plenums 256 to the plurality of patient-side ports 230by controlling the first plurality of control valves 264 and to regulatethe reduced pressure supplied to the plurality of reduced-pressureplenums 256 using the second plurality of control valves 268. Thecontroller 236 is electrically coupled to the electrical power source238.

In one illustrative embodiment, the controller 236 is configured toreceive the plenum pressure signal for each plenum of the plurality ofreduced-pressure plenums 256, and if a plenum pressure signal is lessthan a plenum threshold (for example, without limitation, if −290 mm Hgis less reduced pressure than an illustrative plenum threshold of −300mm Hg) to at least partially open the associated valve of the secondplurality of control valves to deliver additional reduced pressure tothe plenum associated with the plenum pressure signal that is less thanthe plenum threshold. The controller 236 is also configured to receivethe treatment pressure signal for each of the plurality of treatmentpressure sensors 232 and if a treatment pressure signal is less than aminimum treatment pressure threshold (e.g., without limitation, thepressure is −90 mm Hg which is less than the minimum treatment pressureof −100 mm Hg) to at least partially open the associated valve of thefirst plurality of control valves 264 and if the treatment pressuresignal is greater than a high treatment pressure threshold to at leastpartially close the associated valve of the first plurality of controlvalves 264. Each of the plurality of patient-side ports 230 may alsoinclude a relief valve to limit the maximum reduced pressure that may beapplied to a reduced-pressure dressing 214.

The controller 236 may also be operative to prioritize the filling ofthe plenums of the plurality of reduced-pressure plenums 256 such that aplenum having a plenum pressure signal that over time continues below aplenum threshold will be filled only after other plenums of theplurality of reduced-pressure plenums 256. In other words, if thecontroller 236 determines that a leak may be occurring with areduced-pressure dressing 214 or other aspect associated with aparticular plenum, that plenum will be filled last to avoid devoting allor a substantial amount of the system's reduced pressure to trying tocompensate for a leak.

A plurality of indicators 270 (only one shown for illustration purposes)may be associated with each of the patient-side ports 230. Theindicators 270 may be LED lights or other visual indicators. If thecontroller 236 determines that a leak may exist as referenced above, thecontroller 236 may cause the indicator 270 associated with the channelor particular reduced-pressure dressing 214 to be activated. In thisway, the user may be able to address the leak for that particularchannel or reduced-pressure dressing 214.

Numerous alterations and options may be exercised with the system 200.In another illustrative embodiment, the system 200 may be used with adifferent arrangement of reduced-pressure plenums 256 such that perhapstwo channels are operated on one plenum or the system has one largerplenum upon which each channel is fed.

The volume of a reduced-pressure plenum 256 may vary (depending upon thecapacity one wishes to provide and the likely leak tolerance one needsthe system to manage) from about 50 cc at the low end to about 400 cc.Other volumes are possible.

In another illustrative embodiment, the reduced-pressure plenum 256 isadjusted to use mechanical pressure/energy storage. For example, asealed bellow plastic structure of sufficient strength that it is ableto vertically or in some form collapse under a vacuum that is alsocapable of exerting force to return to its previous shape may be used.In this case, the force is essentially multiplied. If one considers sucha structure with a spring structure incorporated (see FIG. 4 ), underhigh reduced pressure the air is removed and the structure is charged.When connected to the wound via the regulating valves, the springattempts to extend and the structure will expand to ‘pump’ negativepressure to the wound. The pressure in the structure or the mechanicalposition of the structure may be monitored in order to determine when are-charge is required. This may be a molded bellows structure or apiston type assembly with a central spring, or alternatively acombination of the aforementioned structures with constant force springssuch that the pressure delivered is predictable.

In another illustrative embodiment, the main vacuum source 266 may beused in conjunction with or replaced with a connection to another pumpsuch as wall-suction or another integrated vacuum source which would beavailable at the place of treatment. Such a system would have theadvantage of requiring less electrical power during operation and wouldin the case of an airborne system be reliant on other flight approvedpumps.

In another illustrative embodiment where the user does not require achange of the regulated pressure setting for each wound, theproportional valves may be replaced with a simple mechanical regulatingvalve which controls the wound pressure. This arrangement would stillprovide for pressure feedback and alarms. With an absorbent baseddressing system, there will be no tube blockages so the system maymerely determine and confirm the appropriate delivery of pressure andalso notify the caregiver when the dressing is full.

Further, if a mechanical valve is used, the valve may be manufacturedand produced such that it is capable of selecting from a range ofpressures. Such a design might include a rotational collar on theregulating valve, which would adjust the spring force on the regulatingdiaphragm such that with less force, a lower pressure is regulated tothe wound, and with a greater force on the diaphragm, a higher pressureis regulated to the wound. The electronic system may be configured torecognize that this pressure has been manually adjusted to eitherpre-set levels (e.g., −75/−125/−200 mm Hg) or to a user selectedvariable pressure (−143 mm Hg for example) by a pressure sensorconnected to the immediate orifice of the regulator and thus providepressure feedback in the knowledge that this pressure is the pressurewhich should be manifolded to the reduced-pressure interface through theabsorbent structure.

In another illustrative embodiment, the higher-vacuum plenum volumecould include the multi-lumen reduced-pressure delivery conduit 226going to the wound site, with final pressure regulation and woundpressure sensing hardware placed at or near each tissue site 202.Regulation would be implemented with a piezo-proportional valve (e.g.,from Festo) which requires relatively little battery power (smallcurrents are required only to change the valve opening, not to maintaina setting). Disposable medical grade pressure sensors (e.g., fromMeasurement Specialties) are available at low cost to incorporate intothe dressing. Wireless communication back to the controller 236 ispossible, and this would provide additional options for usingy-connectors to reduce the number of tube sets running back to the maincontrol unit, and thus reduce the number of plenums required.

In one illustrative embodiment, light may be used to identify channelswith issues. It has been shown that clear extruded tubing makes a goodconduit for light transmission. This can be utilized to highlightindividual conduits by applying a light source to one end, which has theeffect of illuminating the length of conduit much like a fiber optictube, but in this instance the light diffuses along its length. This mayalso be helpful in instructing the user of the location of a fluid orexudate blockage, as one would expect that the transmitted light wouldbe refracted less after such a mass. This would be useful to indicatewhich one of multiple conduits is at issue during a fault condition orwhen setting up the system. As it is expected that the device may beused in noisy environments such as field hospitals and militaryaircraft, this feature may augment the audio feedback that is oftenrelied upon during modes such as seal check. The use of multi-color LEDswould allow for the color to be altered depending on the informationthat was being communicated.

Referring now primarily to FIG. 5 , an illustrative embodiment of asystem 300 for simultaneously treating a plurality of tissue sites 302on a patient 304 is presented. The plurality of tissue sites 302,plurality of reduced-pressure dressings 314, and many other aspects ofthe system 300 are analogous to those in FIGS. 1 and 4 . While numeroustissue sites, sizes, and depths may be treated with the system 200, thesystem 300 is shown treating tissue sites 302 in the form of wounds. Thewounds are shown for illustrative purposes extending through epidermis308, dermis 310, and into subcutaneous tissue 312. Other depths or typesof wounds or, more generally, tissue sites may be treated. While fivetissue sites 302 are shown for illustration purposes, it should beunderstood that any number of tissue sites—typically two or greater—maybe treated with the system 300.

The system 300 includes the plurality of reduced-pressure dressings 314deployed on the plurality of tissue sites 302. Each of the plurality ofreduced-pressure dressings 314 may be any kind of dressing that allowsreduced pressure to be delivered to the tissue site 302 associated withthe reduced-pressure dressing 314 and that is operable to remove fluidsfrom the tissue site 302. In one illustrative embodiment, eachreduced-pressure dressing 314 includes a manifold 316, a sealing member318, and a reduced-pressure interface 320. The sealing member 318 isreleasably coupled to the tissue site 302 using an attachment device322. The attachment device 322 may take numerous forms, such as thosepreviously mentioned in other embodiments. For each tissue site 302, thesealing member 318 creates a sealed space 324 containing the manifold316 and the tissue site 302 to be treated. These components areanalogous to those in FIGS. 1 and 4 .

The reduced-pressure dressings 314 are fluidly coupled to a fluidreservoir 334. The fluid reservoir 334 has a plurality of patient-sideports 330 that are fluidly coupled to a plurality of multi-lumenreduced-pressure delivery conduits 326. The fluid reservoir 334 isfluidly coupled to a reduced-pressure source 350 through areduced-pressure port 351. An internal conduit 353 is fluidly coupledbetween the reduced-pressure port 351 and the reduced-pressure source350. A plurality of by-pass conduits 374 fluidly coupled thepressure-sampling lumens of the multi-lumen reduced-pressure deliveryconduits 326 to a plurality of pressure ports 376. A plurality ofinternal conduits 378 fluidly couples the plurality of pressure ports376 to a multiplexing valve 380. Alternatively, a plurality of controlvalves may be used on a plurality of internal conduits fluidly couplingthe plurality of pressure ports 376 and treatment pressure sensor 332. Acontroller 336 can close all the valves except one at a time to use thetreatment pressure sensor 332 on each valve. The treatment pressuresensor 332 is operatively coupled to the controller 336 to delivertreatment pressure signals.

A fluid storage device is fluidly coupled to each of the plurality ofmulti-lumen reduced-pressure delivery conduits 326. The fluid storagedevice is fluidly coupled to the plurality of reduced-pressure dressings314 for receiving and at least temporarily storing fluids therefrom. Thefluid storage device may be one or more of the following: the fluidreservoir 334 fluidly coupled to each the multi-lumen reduced-pressuredelivery conduits 326 as shown, or a plurality of in-line canisters (notshown but analogous to in-line canister 235 in FIG. 4 )), or a pluralityof absorbent layers associated with or forming part of the plurality ofreduced-pressure dressings 314.

The multi-port therapy unit 328 includes the controller 336 and theplurality of pressure ports 376. Each of the plurality of pressure ports376 is configured to fluidly couple with at least one of thepressure-sampling lumens of the plurality of multi-lumenreduced-pressure delivery conduits 326. The multi-port therapy unit 328further includes the treatment pressure sensor 332 that is fluidlycoupled to the plurality of pressure-sampling lumens associated with theplurality multi-lumen reduced-pressure delivery conduits 326. A valvemeans may be used to couple one of the plurality of pressure ports 376to the treatment pressure sensor 332 at a time. The valve means may bethe multiplexing valve 380 or plurality of valves as described elsewhereherein.

The multi-port therapy unit 328 also includes the reduced-pressuresource 350 that is fluidly coupled to the plurality of reduced-pressuredressings 314. The reduced-pressure source 350 is operatively coupled tothe controller 336. The reduced-pressure source 350 charges the fluidreservoir 334 with reduced pressure that is delivered by the pluralityof multi-lumen reduced-pressure delivery conduits 326 to the pluralityof reduced-pressure dressings 314.

The multi-port therapy unit 328 also includes the controller 336. Thecontroller 336 is operatively coupled to the treatment pressure sensor332, the valve means (e.g., multiplexing valve 380), and thereduced-pressure source 350. The controller 336 is configured to monitorthe treatment reduced pressure signals of each of the plurality ofpressure-sampling lumens associated with the plurality of multi-lumenreduced-pressure delivery conduits 326 as measured by the treatmentpressure sensor 332. In response, the controller 336 controls thereduced pressure delivered by the reduced-pressure source 350 to theplurality of reduced-pressure dressings 314. The controller 336 may beconfigured to determine a number of pressure ports 376 in use and tolook up a gross-flow-rate limit for the number and compare thegross-flow-rate limit to the actual flow rate of the reduced-pressuresource 350 and if the actual flow rate is greater than thegross-flow-rate limit, to activate an alert (audible alarm, visualindicator, or other alert). As described further below, the controller336 may be configured to use various steps to determine if one or moreof the reduced-pressure dressings 314 is leaking. A user interface 340may be used to receive information from or to input commands or datainto the controller 336.

Referring now primarily to FIG. 6 , another illustrative embodiment of aportion of a system 300 for simultaneously treating a plurality oftissue sites 302 on a patient is presented. The system 300 of FIG. 6 isanalogous to the system 300 of FIG. 5 and accordingly some componentsare labeled with reference numerals but not further described here. FIG.6 differs mainly in that instead of a single treatment pressure sensor332, a plurality of treatment pressure sensors 332 are used. Theplurality of pressure ports 376 are fluidly coupled to the plurality oftreatment pressure sensors 332, which each develop a treatment pressuresignal. The plurality of treatment pressure sensors 332 are operativelycoupled to the controller 336 for delivering the treatment pressuresignals to the controller 336. Other aspects of the system 300 areanalogous to FIG. 5 .

With respect to both FIGS. 5 and 6 and other embodiments, a number ofapproaches may be used in configuring the controller 336 to determinewhen a leak likely exists. Two prominent approaches are readily used.With reference to FIG. 7 , the first includes stopping the reducedpressure to the reduced-pressure dressings 314 and then comparing itsdecay pattern 400 to a set standard or a median decay pattern 402. Ifthe variation is greater than a desired threshold, the controller 336activates an alert. With references to FIG. 8 , the second approach isto stop the reduced pressure supplied to the reduced-pressure dressing314 for a time period and then to activate the reduced pressure andcapture the ramp-up pattern 500 for a particular reduced-pressuredressing 314. This approach may be combined with the initial pressuredecay test to provide dual confirmation of the leaking channel. Theramp-up pattern 500 may then be compared to a standard or median pattern502.

In most illustrative embodiments, the controller 336 may begin with aprocess of auto-detection in which wounds are connected by measuring theon-set of pressure during pull down. Each channel is isolated by asealing valve or membrane at the connection port that is opened onapplication of the wound care disposable. If a channel is found to notbe responding, the user is informed at the start of therapy to that thechannel is not connected (cannot be a leak as all channels will be low).The system takes the number of dressings connected into account when itdetermines the leak alarm threshold (e.g., 1 wound=1 l/min at 125 mmHg,5 wounds=2l/min at 125 mm Hg, and proportional to the number of woundports connected).

To prevent reflux of fluids from the fluid reservoir 334 to themulti-lumen reduced-pressure delivery conduits 326, a simple blockingfeature may be added, such as a piece of open-celled foam, across theentry ports 330 so that fluid splashes do not have the opportunity ofreaching the opening but fluids can be drawn into the fluid reservoir334. As there is a typically a pressure gradient through the system 300with the greater reduced pressure in the fluid reservoir 334 andreducing down towards the dressing 314, it is not anticipated that flowwill naturally occur towards the dressing 314. Alternatively or inaddition, a simple flap valve could be constructed at the port 330 froma material that is permeable to fluids so that therapy is notcompromised but will resist an instantaneous burst of fluid as couldhappen if the fluid reservoir 334 was agitated or knocked over.

With reference again primarily to FIG. 5 , according to an illustrativeembodiment, a single pressure sensor 332 is controlled and multiplexedto measure pressure in a pressure-sampling lumen of each multi-lumenreduced-pressure conduit in sequence. The controller 336 willautomatically assign a percentage of sensor time to each wound, and viaa directional control valve (such as an electronically actuated pistonor spool valve) will pneumatically connect the sensor to each woundevery 2 seconds (sample time may vary). The pneumatic volume between thevalve and the sensor may be minimized to reduce the potential for thechannels to be influenced by each other at switching. Initially this maybe on a purely sequential basis (i.e. wound 1, wound 2, etc), but as thesystem 300 runs its tests, the system 300 may determine that some woundsare struggling to maintain pressure more than others, which areremaining consistent. At this time the controller may choose toprioritize these low performing wounds for more regular checks (i.e.wound 1, wound 2, wound 3, wound 2, wound 4, wound 2 . . . wound 2 has alower pressure). Having one pressure sensor does mean that anysensor-to-sensor variances will not be a factor when the system istrying to balance the wound pressure control. The control valveswitching sequence may be coordinated with a purge function in order toavoid concerns of possible cross-contamination during switching, butalso to reduce the total number of valves required.

Referring again primarily to FIG. 6 , according to one illustrativeembodiment, a plurality of treatment pressure sensors 332 aremultiplexed into one sensor port on the controller 336 which areelectronically scanned by the controller in a manner similar to thosepreviously discussed. Sensor to sensor variances may be a factor in thereporting of channel pressures, but there is a benefit here in that afailure of any one pressure sensor can be reported and that channelindicated as off to the user. In another illustrative embodiment,instead of multiplexing the signals from the treatment pressure sensors332, the controller 336 may monitor each signal continuously.

In an illustrative embodiment, the controller 336 monitors woundpressure measured by the pressure sensor(s) via any of the methods aboveand determines if there is a blockage in the communication of pressurefrom the fluid reservoir 334 to the tissue site 302. In the instance ofthe use of an absorbent dressing or in-line fluid storage, this may beused to indicate that the absorbent is full. Further, by trending thelevel of pressure communication reduction over time (pressure-drop), thecontroller 336 is capable of predicting the level of fill of theabsorbent (Canister pressure−Wound pressure−Leak Overhead=PressureDrop). By trending this pressure drop calculation on achannel-by-channel basis during therapy, the controller 336 can warn thecaregiver not only when the absorbent is full, but also when it is nearto being full.

In one illustrative embodiment, the system 300, which has areduced-pressure source 350 that is a vacuum pump and fixed fluidreservoir volume, is capable of detecting a leak in one or morereduced-pressure dressings 314. The leak is determined by measuring thefluid reservoir pressure and estimating air flow based on pump duty, andcomparing the estimated air flow based on pump duty to pre-determinedair flow levels within the software of the air flow level that should berequired for a set number of wounds.

For example and without limitation, the system 300 may have a leaktolerance of 1 l/min with one or possibly 2 wound dressings. As anotherexample, the system 300 with up to 5 wounds may have a proportionatelyhigher leak threshold as each dressing presents its own sealingchallenge, e.g., a leak tolerance of 2 l/min. The system 300 takes thenumber of dressings connected into account when the controller 336determines the leak alarm threshold (e.g., 1 wound=1 l/min at 125 mm Hg,5 wounds=2 l/min at 125 mm Hg and proportional to the number of woundports connected). Thus, the controller 336 is capable of providing analarm to tell the caregiver if the net average pressure in the system islow, and that a leak likely exists due to the pump having to operate ata level consistent with there being a flow of air into the system thatis above its pre-determined threshold. The system 300 is pneumaticallycapable of delivering therapy with up to 5 dressings or another desirednumber with consideration given not only due to the possibility of airleak, but also because pneumatically a high flow of fluid in the systemimposes the same duty on the pump. A situation may exist where all 5wounds are moderately exudating and there are small leaks which inthemselves would not trigger a leak alarm, but combined with the fluidpressure drop results in the leak alarm threshold being triggered.Therefore, the trigger level may be varied by user input.

In some illustrative systems, the pump control and the multi-channelwound pressure measurements are used to determine which dressings havethe most significant leak. Essentially, this system monitors the woundpressure during deliberate dynamic changes in pump pressure to look fordifferences in the ways in which wound pressure changes betweendressings, to seek ways to identify which one possesses an air leak, forexample, as described with respect to FIGS. 7 and 8 .

In another illustrative embodiment, a two-cavity (or two-chamber)canister, where the cavity acts as a plenum to allow the user to havetwo groups of wounds at different pressures, may be used. Valves areused to allow the single pump to control pressure in these two chambers.

In another embodiment that is an alternative to FIG. 5 , which uses onemultiplexing valve 380, each conduit may have its own electronicallyactuated valve which is driven by the controller 336. When the valvesare closed, they seal the line to prevent leaks. These valves may bedriven directly from the main controller 336 or by a secondary PWA whichhas an encoder circuit driven by a serial connection from the controllerPWA. This would then allow a leaking dressing to be isolated whiletherapy is maintained to the others until the user has corrected thefault.

The embodiments shown in FIGS. 5 and 6 feature collection of fluids in acentralized fluid reservoir 334. The use of a wound-site or an in-lineabsorbent component may be used to replace or augment the capacityprovided by the fluid reservoir 334. This may be used where there aremultiple highly exudating wounds.

In another illustrative embodiment, the systems 300 may use evaporationto further process fluids. The evaporation could be used to enhance thevolume of fluids that can be accepted. A highmoisture-vapor-transfer-rate (MVTR) material is used in thereduced-pressure dressings 314 or at other locations. An aspect of thefluid reservoir 334 may be formed from the high MVTR material. In apressurized cabin, it is normal for the humidity levels to be lower than50% and for the actual pressure to be considerably lower than thatexperienced at sea level—both these factors will aid in the process ofevaporation.

Assisting the user to identify which wound is attached to which channelor port on the canister will greatly help the user locate any wound thatthe device has shown to be blocked or leaking. In the simplest form, theuser may simply mark the wound dressing “1”, “2”, “3” etc. to coincidewith the port number on the fluid reservoir. In low light situations, orwhere there is limited time to apply dressing identification, it may notbe clear which wound is connected to which canister port. Therefore eachport may be fitted with a clear plastic ring that is illuminated from alight source such as a LED, which may be white or color coded for eachport (i.e., a different color for each port). The light sourceilluminating the ring is controlled by the controller 336. The ring willeither be in close proximity or touching the multi-lumenreduced-pressure delivery conduit such that a light connection is madewith the conduit and that when the ring becomes illuminated light isalso fed down the conduit. When an alarm is triggered for port “1”, forexample, the ring on that port illuminates and flashes to indicate whichport is impacted, and the light will also travel down the conduit toassist in highlighting to the user which wound is involved.

The systems 100, 200, 300 or aspects of the systems for simultaneouslytreating a plurality of tissue sites on a patient may be structured innumerous ways. A few illustrative examples follow. Referring for exampleprimarily to FIGS. 9-11 , a multi-port therapy unit 600 is presented.The multi-port therapy unit 600 has a carrying handle 602 and a body604. The body 604 is configured to receive a plurality of canisters 606on a backside 608. Each canister 606 includes a fluid reservoir and aport 607 for receiving a multi-port reduced-pressure delivery conduit.The canisters 606 may include seals for interfacing with the body 604and may clip to a support or attachment prong (not explicitly shown) orotherwise releasably attached to the body 604.

Reduced pressure is supplied from a vacuum pump within the body 604 toeach canister 606. Additionally, a pressure sensor (e.g., pressuresensor 132 in FIG. 2 ) is fluidly coupled to the pressure-sampling lumenof the associated multi-port reduced-pressure deliver conduit. Thesevarious configurations and operational aspects may be as thosepreviously presented for the various illustrative embodiments. A frontface 610 includes a user panel 612, or user interface. The user panel612 may have segments 614 devoted to each of the plurality of canisters606. The back side 608 may include a pole-attachment device 616 forreleasably attaching the multi-port therapy unit 600 to a pole or othersecuring member. The pole-attachment device 616 may include a polechannel 617 and a knob 618 to screw a clamp onto the pole in the polechannel 617 or other securing member.

Referring now primarily to FIGS. 12-15 , another multi-port therapy unit600 is presented. The multi-port therapy unit 600 is analogous in mostrespects to the multi-port therapy unit 600 of FIGS. 9-11 , andaccordingly, some parts are labeled but not further described here. Amain difference between the multi-port therapy unit 600 of FIGS. 12-15and the multi-port therapy unit 600 of FIGS. 9-11 is that the pluralityof canisters has been moved to the front face 610. In FIG. 12 , anillustrative multi-lumen reduced-pressure delivery conduit 620 is showncoupled to the port 607 associated with one canister 606.

Referring now primarily to FIGS. 16-18 , another multi-port therapy unit600 is presented. The multi-port therapy unit 600 is analogous in mostrespects to the multi-port therapy unit 600 of FIGS. 9-11 , andaccordingly, some parts are labeled but not further described here. Amain difference between the multi-port therapy unit 600 of FIGS. 16-18and the multi-port therapy unit 600 of FIGS. 9-11 is that the canisters606 are coupled to the body 604 on a first side 622. For illustrationpurposes, one multi-lumen reduced-pressure delivery conduit 620 is showncoupled to a port 607 of one canister 606. Also shown is a power cordconnection 624.

Referring now primarily to FIGS. 19-21 , another multi-port therapy unit600 is presented. The multi-port therapy unit 600 is analogous in mostrespects to the multi-port therapy unit 600 of FIGS. 9-11 , andaccordingly, some parts are labeled but not further described here. Amain difference between the multi-port therapy unit 600 of FIGS. 19-21and the multi-port therapy unit 600 of FIGS. 9-11 is that the canisters606 are coupled on a first side 622 and a second side 626. In addition,the canisters 606 on each side 622, 626 are staggered vertically (fororientation shown). The canisters 606 have a kidney shape that may beoriented differently on each side 622, 626. FIG. 21 shows fourmulti-lumen reduced-pressure delivery conduits 620 coupled to themulti-port therapy unit 600. A canister channel 628 to receive anattachment prong is shown in FIG. 19 .

Although the present invention and its advantages have been disclosed inthe context of certain illustrative, non-limiting embodiments, it shouldbe understood that various changes, substitutions, permutations, andalterations can be made without departing from the scope of theinvention as defined by the appended claims. It will be appreciated thatany feature that is described in connection to any one embodiment mayalso be applicable to any other embodiment.

It will be understood that the benefits and advantages described abovemay relate to one embodiment or may relate to several embodiments. Itwill further be understood that reference to “an” item refers to one ormore of those items.

The steps of the methods described herein may be carried out in anysuitable order, or simultaneously where appropriate.

Where appropriate, aspects of any of the embodiments described above maybe combined with aspects of any of the other embodiments described toform further examples having comparable or different properties andaddressing the same or different problems.

It will be understood that the above description of preferredembodiments is given by way of example only and that variousmodifications may be made by those skilled in the art. The abovespecification, examples and data provide a complete description of thestructure and use of exemplary embodiments of the invention. Althoughvarious embodiments of the invention have been described above with acertain degree of particularity, or with reference to one or moreindividual embodiments, those skilled in the art could make numerousalterations to the disclosed embodiments without departing from thescope of the claims.

We claim:
 1. A multi-port therapy unit for treating a tissue site withreduced-pressure, the multi-port therapy unit comprising: a fluidreservoir; at least two side ports disposed on an exterior of themulti-port therapy unit and each side port configured to fluidly coupleto a delivery conduit, each side port fluidly coupled to the fluidreservoir; a controller; at least two pressure sensors operativelycoupled to the controller, directly coupled to a respective side port ofthe at least two side ports and configured to generate a pressure signalcorresponding to a pressure at the respective side port; and anindicator operatively coupled to the controller and configured todisplay a status of a respective side port; and wherein the controlleris configured to receive the pressure signal of a side port, determinethe status of the side port in response to the pressure signal, andoperate the indicator to display the status.
 2. The multi-port therapyunit of claim 1, wherein the indicator is a user interface.
 3. Themulti-port therapy unit of claim 1, wherein the indicator is a pluralityof light emitting diodes operable to provide a color indication ofpressure in response to the status determined by the controller.
 4. Themulti-port therapy unit of claim 1, wherein the indicator is a pluralityof indicators, each side port having a first indicator, a secondindicator, and a third indicator, each indicator configured to display astatus.
 5. The multi-port therapy unit of claim 1, wherein the indicatoris a plurality of indicators, each side port having a first indicator, asecond indicator, and a third indicator, wherein: the first indicator isconfigured to display a green light and is operated by the controllerwhen pressure at a respective side port is between about −75 mm Hg andabout −150 mm Hg; the second indicator is configured to display a yellowlight and is operated by the controller if the controller determinesthat the pressure signal for the respective side port indicates therespective side port is losing reduced pressure; and the third indicatoris configured to display a red light and is operated by the controllerto display a continuous red light when the pressure at the respectiveside port is not providing adequate therapy and is operated by thecontroller to display a flashing red light when the pressure at therespective side port is an over pressure.